My friend came to me for mileage/credit card advice... and of course I immediately turn to flyer talk haha.

My friend is based in SFO. He plans on flying to Singapore 3~4 times a year and to TPE at least once a year. He also travels for business within US and sometimes to Europe, but these are sporadic and very hard to predict.

He wants to know which airline mileage program he should join. I looked on ITA Matrix and it seems like Singapore Airline and United serves the route the most. And Eva has a direct route from SFO to TPE. It seems like it makes the most sense to choose a star alliance program. My first instinct was United, but then I remembered that United is adapting that new airfare-based earning model.

So I think Singapore or Eva would probably the best bet? Which of these two would be better? Or are there better programs that I should consider?

Thanks!